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Note 11 - Stock-based Compensation (Detail) - Assumptions Used in the Determination of Fair Value of Share-Based Payment Awards	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Expected term	5 years	3 years 9 months
Risk-free interest rate		0.89%
Expected volatility		1.03%
Expected dividend yield	0.00%	0.00%

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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